Music test:
Enter MUSIC_ON as a name at the character screen for either the main character or a character that you are buying.

Delete saved data:
Enter DEL_DATA as a name at the character screen for either the main character or a character that you are buying to delete all current files.

Character and item duplication:
Note: This trick requires a link cable and another Tactics Ogre game. Make a backup save of the character and items to be duplicated. Go into your backup save. Trade off your item or character with the other game then reset your game. Reload it then load your original game and trade off again to get your character or item. Repeat this as many times as needed.

Lock all characters except the one to be duplicated. Equip the character to be duplicated with any weapons/armors/spells that you want to duplicate. Hire two soldiers (or use any two that you do not care if lost) and put them at the end in "XYZ" order, with the one to be duplicated last "Z". Get into a fight, using character "Y" in the battle and allow him to be killed. This does not have to be real battle, however if its training the character has to use a Snapdragon. After winning the battle, go to the menu, select "Sort" then "Execute". Confirm it, then cancel all the way out by pressing B. Go to any shop and sell all equipment that the duplicated character had equipped, including spells. To sell the items, sell 99 of it, then sell 58 plus however many you originally had and you will end up with 99 of that item. When done, you will have two characters with the same stats, name, items, and 99 of all equipment and spells that character had originally had, plus more money.